""An early ether vaporizer designed by John Snow. A Treasure of the Wood Library-Museum of Anesthesiology.""
PDF posted with permission from the Wood Library-Museum, Schaumburg IL (USA).
At the time, it appeared that the apparatus at the WL-M was "the single surviving Snow vaporizer" (99). In 2009, however, Connor and Zuck determined that the Royal Society of Medicine (UK) owned a similar model.